1. Field of the Invention
The present invention relates to a pressure-sensitive adhesive composition, a conductive film, a touch panel and a pressure-sensitive adhesive film.
2. Discussion of Related Art
A touch panel is called a touch screen and applied to various data processing terminals such as a mobile communication terminal or ATM, or displays such as a TV or monitor.
For such a touch panel, a conductive film in which a conductive layer is formed on one or both surfaces of a substrate by depositing a conductor such as indium tin oxide (ITO) may be used as a basic unit part.
In the manufacture of the touch panel, a pressure-sensitive adhesive may be used to attach the conductive film to an adherent, or form a stacked structure by stacking a conductive film. Such a pressure-sensitive adhesive is maintained transparent under severe conditions such as high temperature, high temperature and humidity, or a serious change in temperature or humidity, and requires physical properties which do not induce lift-off, peeling and curling.
Meanwhile, as the substrate of the conductive film, a plastic substrate may be used. However, the plastic substrate induces an out-gassing phenomenon in which moisture, solvents or other additives in the plastic substrate are emitted in a gas form under a heating condition. Since the emitted gas creates bubbles and thus reduces visibility, when a pressure-sensitive adhesive is in contact with the plastic substrate, the generation of bubbles from the substrate should be prevented.
In addition, when the pressure-sensitive adhesive is directly adhered to the conductive layer of the conductive film, the pressure-sensitive adhesive layer serves to prevent a resistance change in the conductive layer even when being used under severe conditions, and ensure stable drive for a long time.